Oval EX DELTA II, Инструкция по эксплуатации

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D-583-2N-E
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5. PIPING INSTRUCTIONS
For general considerations to be observed, see JIS Z 8766, "Flowrate Measurement Methods with Vortex
Flowmeters".
5.1 Standard Piping Conditions
NOTE: A downstream straight pipe 5D or longer is required.
It is generally required that the flow pattern of the fluid flows through an inferential type meter be as uniform
as possible for precise metering. Accordingly, proper flow straightening measures must be taken when the
application engineer considers installation of a DELTA Flowmeter. In applications where OVAL straightening
devices (flow straightener, honey vane, and downstream pipe) are used, a straight pipe section is not required
unless otherwise specified. But if you plan to solve the flow pattern problem with a straight pipe section alone,
secure the length of a straight pipe conforming to the ISO standards given in Table 5. below:
(1) OVAL flow straightener combined with downstream pipe (25mm and up in nom. dia.)
D = Nom. Dia.
No. Remarks
Honey vane L
8D
Flow
See Fig. 5. on page .
2 Flow Straightener
12D
Flow
See page 46 for face-to-face dimension.
(2) Straight pipe alone without flow straightener
Table 5. Straight Pipe Lengths Recommended by ISO-567
D = Nom. Dia.
No. Remarks
Reducer
15D more
Flow
A concentric reducer is upstream of meter.
2 Elbow
23D more
Flow
An elbow is upstream of meter.
25D more
Flow
Two elbows are horizontally upstream of
meter.
40D more
Flow
Two elbows are vertically upstream of meter.
3
Gate Valve
Fully Open
15D more
Flow
Fully Open
A full-open gate valve is upstream of meter.
4
Gate Valve
Partially Open
50D more
Flow
Partially
Open
A partially open gate valve, a narrow orifice,
or something that considerably disturbs the
flow pattern is upstream of meter.